Polishing jig, conveyor tray, conveying method and conveying device

ABSTRACT

A polishing jig for mounting a working object lens on a polishing apparatus that polishes the concave surface of the working object lens, a conveyor tray for exclusive use for conveying the polishing jig, and a conveying method and a conveying apparatus for conveying the polishing jig or the like with the working object lens held thereon to a working apparatus such as the polishing apparatus. The polishing jig ( 1 ) includes a mounting potion ( 2 ) to be mounted on a chuck of a polishing apparatus, a ring-shaped closely contacting portion ( 3 ) for closely contacting with a convex surface ( 11 ) of a working object lens ( 10 ), and a filling gap portion ( 4 ) having an opening at the closely contacting portion for being filled with adhesive substance ( 7 ) which adheres to the convex surface of the working object lens closely contacted by the closely contacting portion to hold the working object lens.

This is a National stage entry under 35 U.S.C. § 371 of PCT ApplicationNo. PCT/JP02/07518 filed Jul. 25, 2002; the above noted application ishereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a polishing jig for mounting a workingobject lens on a polishing apparatus that polishes the concave surfaceof the working object lens, a conveyor tray for exclusive use forconveying the polishing jig, and a conveying method and a conveyingapparatus for conveying the polishing jig or the like with the workingobject lens held thereon to a working apparatus such as the polishingapparatus.

BACKGROUND ART

In recent years, an inner surface progressive multi-focal lens having aprogressive face on the concave surface side (inner surface side) of aspectacle lens has been developed. The inner surface progressivemulti-focal lens can reduce the image jump and the distortion which aredefects of a progressive multi-focal lens which has a progressive faceon the convex surface side thereof, and can raise the opticalperformance remarkably.

Polishing of a spectacle lens for generating an optical surface in theform of a concave surface of such an inner surface progressivemulti-focal lens as described above forms the concave surface of theworking object lens into a predetermined optical surface throughcutting, grinding, mirror polishing and so forth. Such a numericallycontrolled machining apparatus as shown in FIG. 10 has been developed asa polishing apparatus which can cut the concave surface of a spectaclelens.

Processing data for numerical control calculated by a computer forcalculation based on prescription data for a spectacle lens inputtedfrom an inputting apparatus is transmitted to the numerically controlledmachining apparatus 600 through a host computer and stored into aninternal storage apparatus of the numerically controlled machiningapparatus 600.

The numerically controlled machining apparatus 600 includes an X-axispositioning mechanism 610 and a Y-axis positioning mechanism 620 on abed 601. The X-axis positioning mechanism 610 is driven to move in asubstantially horizontal X-axis direction by an X-axis driving motor andan encoder 611. The position of the X-axis positioning mechanism 610 inthe X-axis direction is indexed by the encoder 611. A work shaftrotating mechanism 612 is secured on the X-axis positioning mechanism610 and has an axis of rotation coincident with a substantiallyhorizontal Y-axis direction perpendicular to the X axis. A chuck 613 isattached to the work shaft rotating mechanism 612 and driven to rotateby a work rotary shaft driving motor and an encoder 614. The rotationalposition of the chuck 613 is indexed by the encoder 614. A workingobject lens (work) 10 is attached to the chuck 613 through a block jig.The Y-axis positioning mechanism 620 is driven to move in the Y-axisdirection by a Y-axis driving motor and an encoder 621. The position ofthe Y-axis positioning mechanism 620 in the Y-axis direction is indexedby the encoder 621. Two cutting tool holders including a first cuttingtool rest 622 and a second cutting tool rest 623 are secured on theY-axis positioning mechanism 620, and a roughing cutting tool 624 issecured to the first cutting tool rest 622 while a finishing cuttingtool 625 is secured to the second cutting tool rest 623.

According to a controlling method, the center coordinates of a tip endof the cutting tool 624 or 625 are positioned in a normal direction to aworking point of the work 10 using the three axes of the X-axispositioning mechanism 610, Y-axis positioning mechanism 620 and workshaft rotating mechanism 612. Then, the positioning of the centercoordinates of the tip end of the cutting tool corresponding to theworking point is performed continuously to perform shape generationbased on a lens design shape. At this time, the work 10 is rotated at aspeed within 100 to 6000 rpm depending upon the shape of the work andthe type of working between roughing and finishing by the work shaftrotating mechanism 612. The rotational position of the work 10 isindexed by the encoder 614, and the Y-axis positioning mechanism 620 andthe X-axis positioning mechanism 610 are positioned in synchronism withthe rotation of the work 10. In particular, while the work 10 isrotated, the relative positions between the cutting tools 624 and 625and the work 10 in the direction of the Y axis coincident with the axisof rotation of the works 10 and the relative positions between thecutting tools 624 and 625 and the work 10 in the X-axis direction aresynchronized with the rotation of the work 10.

The numerically controlled machining apparatus 600 changes over betweenthe roughing cutting tool 624 and the finishing cutting tool 625 toperform a shaving process.

The numerically controlled machining apparatus 600 having such aconfiguration as described above can generate any surface shape and canperform shape generation of an inner surface progressive multi-focallens.

Conventionally, such a block jig as shown in FIG. 11 is used as theblock jig for mounting the working object lens 10 on the chuck 613 ofthe numerically controlled machining apparatus 600.

The block jig 400 shown includes a mounting portion 410 for mounting theblock jig 400 on the chuck 613 of the machining apparatus 600, and a lowmelting point metal portion 420 for coupling the mounting portion 410and the working object lens 10 to each other. The low melting pointmetal portion 420 is formed using a ring-shaped jig not shown as a moldby interposing the ring-shaped jig between the mounting portion 410 andthe working object lens 10, filling molten metal having a low meltingpoint into a gap of the ring-shaped jig, leaving the low melting pointmetal to be solidified and then removing the ring-shaped jig.

However, such a block jig 400 as described above is not necessarilysuitable for the numerically controlled machining apparatus 600 becausea block jig which has been used in a conventional polishing apparatuswhich uses rubbing is used as it is as the block jig 400 in thenumerically controlled machining apparatus 600.

For example, when the mounting portion 410 is mounted and set inposition on the chuck 613 of the numerically controlled machiningapparatus 600, the reference for machining is provided by the angularityof a corner portion 430 at which the mounting portion 410 intersectswith the low melting point metal portion 420 which uses a ring-shapedjig as a mold. However, a gap or the like appears between the mountingportion 410 and the low melting point metal portion 420 due toappearance of a cavity in or shrinkage of the low melting point metalportion 420. Therefore, the block jig 400 has a problem in that theangularity of the corner portion 430 cannot readily be formed accuratelyand numerically controlled mashing of a high degree of accuracy isdifficult.

On the other hand, where the numerically controlled machining apparatus600 is used, it is possible to automatically perform a series ofprocesses of incorporating a conveying apparatus, carrying in andmounting a polishing jig having a working object lens held thereon onthe chuck, performing polishing of the working object lens and thencarrying out the polishing jig with the worked lens held thereon.

However, the conventional block jig 400 is not ready for such automaticconveyance.

Therefore, it is demanded to develop a novel polishing jig suitable forthe numerically controlled machining apparatus 600 which performs shapegeneration of the concave surface of an inner surface progressivemulti-focal lens.

Also a conveyor tray for exclusive use is required which can accommodateand protect such a polishing jig as just described with a working objectlens held thereon and is ready for automation of a numericallycontrolled machining apparatus.

A numerically controlled machining apparatus can perform fully automaticpolishing if a step of conveying a polishing jig with a working objectlens held thereon to a polishing apparatus, another step of conveyingthe polishing jig with the worked lens held thereon to a next step andother necessary steps can be automated.

However, polishing of a spectacle lens involves special conditions. Forexample, usually a pair of left and right spectacle lenses are workedtogether. Also after polishing, it is demanded that a pair of left andright spectacle lenses be fed through a dyeing step, an inspection step,a packing step and so forth. Therefore, it is demanded to use a conveyortray which accommodates a pair of left and right lenses. Besides, it isdemanded that, upon polishing of a pair of left and right lenses, theymay not be brought out of the paired relationship.

Further, in polishing of a lens by the numerically controlled machiningapparatus 600, several minutes are required for working of one lens.Therefore, a one-by-one successive working method wherein working objectlenses are taken out one by one from a conveyor tray and worked and alens whose working is completed is conveyed back to its originalposition of the conveyor tray, whereafter another working object lens isconveyed into the polishing apparatus has a problem in that theefficiency is low.

The present invention has been made in view of such circumstances asdescribed above, and it is a first object of the present invention toprovide a polishing jig suitable for a numerically controlled machiningapparatus.

It is a second object of the present invention to provide a conveyortray for exclusive use for conveying a polishing jig of the typedescribed.

It is a third object of the present invention to provide a conveyingmethod wherein working object articles can be worked efficiently by aworking apparatus which requires a long period of time for working whilethey are kept accommodated in pair in a conveyor tray of the typedescribed.

It is a fourth object of the present invention to provide a conveyingapparatus which can implement a conveying method of the type described.

DISCLOSURE OF INVENTION

In order to attain the first object described above, the polishing jigof the present invention has such a structure that a ring-shaped jig ofa conventional block jig is integrated with a mounting portion. Inparticular, one of the reasons by which a conventional block jig uses aring-shaped jig is that it is intended to perform eccentric working oraddition of a prism by means of a conventional polishing apparatus whichuses rubbing, and it is necessary to prepare a large number ofring-shaped jigs ready for such eccentric working and addition of aprism. However, with a numerically controlled machining apparatus, sinceeccentric working and addition of a prism can be performed through aprogram, it is not necessary to prepare a large number of ring-shapedjigs for such objects as described above. Further, since the convexsurface side of an inner surface progressive multi-focal lens has aspherical surface or a rotationally symmetric aspheric surface, in orderto keep the convex surface, only several different ring-shaped jigs arerequired. Therefore, it is possible to integrate a ring-shaped jig witha mounting portion.

Consequently, a corner portion which is used as a reference forpolishing can be formed as part of a polishing jig, and therefore, theworking accuracy is high.

Further, where the polishing jig further has a gripping portion whichprojects outwardly farther than the working object lens in a directionsubstantially perpendicular to a rotational center axis of the mountingportion, it is possible for a robot hand to grip the gripping portion ofthe polishing jig and convey the polishing jig. Consequently, thepolishing jig can be conveyed automatically.

Further, where a first engaging portion for positioning is provided onthe gripping portion, the position of the polishing jig in therotational direction can be determined accurately using the firstengaging portion as a reference position for positioning, and this cancontribute to automation.

Furthermore, where a turning preventing projection or recess is providedon a wall face which defines the filling gap portion into which adhesivesubstance such as metal having a low melting point is to be filled, whenthe filled adhesive substance is exfoliated from the wall face of thefilling gap portion, motion of the same in the rotational direction issuppressed. Therefore, accurate working can be anticipated.

Similarly, where a reverse taper for pull-out prevention portion isprovided on a wall face which forms the filling gap portion, when thefilled adhesive substance is exfoliated from the wall face of thefilling gap portion, the adhesive substance can be prevented from comingoff from the filling gap portion.

In order to attain the second object, a conveyor tray of the presentinvention has an accommodation section for receiving an outer peripheralportion of the gripping portion of the polishing jig, a through-hole forpassing therethrough an ejecting jig which receives the polishing jigplaced on the accommodation portion and moves up and down together withthe polishing jig, and a second engaging portion for engaging with thefirst engaging portion of the gripping portion so that the polishing jigmay be positioned and accommodated accurately.

Further, since left and right spectacle lenses are in most casespolished in pair, preferably the conveyor tray is configured so as toaccommodate two polishing jigs therein.

In order to achieve the third object, according to a conveying method ofthe present invention, while a working object article is being worked bya working apparatus, another working object article is left in a standbystate for working, and a worked article for which working is completedis returned to an original accommodation position of the conveyor tray.Consequently, working can be performed efficiency by the workingapparatus even if the working apparatus has a long period of time forworking. Further, a pair of working object articles accommodated in aconveyor tray are worked by the working apparatus while they are kept inpair.

In particular, when working is completed, the worked article for whichthe working is completed is carried out, and another working objectarticle which has been in a standby state is mounted on the mountingapparatus to start working thereof. Then, while the working objectarticle is being worked, the worked article is returned to its originalaccommodation position of the conveyor tray, and a next working objectarticle is taken out from the conveyor article and conveyed into theworking apparatus so that it thereafter remains standby in the workingapparatus. Consequently, a working object article can be mountedrapidly, and besides conveyance can be performed within a period of timeof working to perform working efficiency. Further, since a workedarticle is returned to its original position of the conveyor tray, thepair can be maintained.

Where a working object article accommodated in the conveyor tray istaken out at a predetermined transfer position and the worked article isreturned to the original accommodation position of the conveyor tray atthe transfer position, the conveying apparatus can be made comparativelysimple and easy.

Further, in order to attain the fourth object, a conveying apparatus ofthe present invention is configured so as to have the following transfermeans and conveying means thereby to implement the conveying methoddescribed above. In particular, the transfer means takes out a workingobject article from a conveyor tray at a particular transfer positionand conveys the working object article to a working apparatus so thatthe working object article thereafter stands by in the workingapparatus, takes out a worked article for which working by the workingapparatus is completed, mounts the working object article in the standbystate on the working apparatus, and conveys and accommodates the workedarticle into the conveyor tray at the transfer position. The conveyingmeans controls the position of the conveyor tray such that, when thetransfer means conveys the worked article to the transfer position, theaccommodation position in which the worked article was accommodated isdisposed at the transfer position.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows an embodiment of a polishing jig of the present invention,and wherein (a) of FIG. 1 is a plan view, (b) of FIG. 1 is a sectionalview taken along line A–A′ of (a) of FIG. 1, and (c) of FIG. 1 is abottom plan view;

FIG. 2 is a sectional view showing, in an enlarged scale, an embodimentof a closely contacting portion of the polishing jig of the presentinvention;

FIG. 3 is a sectional view showing the polishing jig of the presentinvention in a state wherein it holds a working object lens thereon;

FIG. 4 shows an embodiment of a conveyor tray of the present invention,and wherein (a) of FIG. 4 is a top plan view, and (b) of FIG. 4 is asectional view taken in a direction perpendicular to the top plan;

FIG. 5 is an arrangement plan showing an arrangement of a numericallycontrolled machining apparatus for spectacle lenses and a conveyingapparatus for conveying a working object article to the machiningapparatus;

FIG. 6 is a side elevational view of a conveyor tray on a conveyor asviewed in a direction in which the conveyor tray is moved forwardly andbackwardly;

(a) of FIG. 7 is a sectional view of polishing jigs, each of which holdsworking object lenses accommodated in a conveyor tray, in a statewherein it is conveyed to the machining apparatus;

(b) and (c) of FIG. 8 are sectional views showing the working objectlenses, which are held on the polishing jigs accommodated in theconveyor trays, in a state wherein they are transported to and machinedby the machining apparatus;

(d) and (e) of FIG. 9 are sectional views showing the working objectlenses, which are held on the polishing jigs accommodated in theconveyor trays, in a state wherein they are transported to and machinedby the machining apparatus;

FIG. 10 is a schematic diagrammatic view of a general configurationshowing an embodiment of a numerically controlled machining apparatus;and

FIG. 11 is a sectional view showing a conventional block jig.

BEST MODE FOR CARRYING OUT THE INVENTION

In the following, embodiments of a polishing jig, a conveyor tray, aconveying method and a conveying apparatus of the present invention aredescribed with reference to the drawings.

An embodiment of the polishing jig of the present invention is describedwith reference to FIGS. 1, 2 and 3.

The polishing jig 1 shown includes a mounting portion 2 for beingmounted on a chuck 613 of a polishing apparatus such as the numericallycontrolled machining apparatus 600 shown in FIG. 10, a closelycontacting portion 3 having a short-axis cylindrical shape for closelycontacting with a convex surface of a working object lens, and aring-shaped portion 5 for connecting the closely contacting portion 3and the mounting portion 2 to each other and forming a filling gapportion 4 which has an opening at the closely contacting portion 3 andinto which adhesive substance is to be filled.

The polishing jig 1 is made of a metal such as aluminum and is formedbasically in a rotationally symmetrical form around a rotational centeraxis 21 of the mounting portion 2.

The mounting portion 2 has a hollow portion 22 along the rotationalcenter axis 21, and a portion of the mounting portion 2 lower than acylindrical portion 23 formed in a thick cylindrical shape has a taperedportion 24 provided thereon such that the thickness thereof decreasesdownwardly. A diametrical recess 25 is formed on the bottom of thetapered portion 24 and passes the rotational center axis 21. Anotherportion of the mounting portion 2 higher than the cylindrical portion 23forms a disk portion 26 having a rather increased diameter in adirection perpendicular to the rotational center axis 21. An outer faceof the cylindrical portion 23 and a lower face of the disk portion 26are provided such that they extend orthogonally to each other.

The mutually orthogonal faces of the cylindrical portion 23 and the diskportion 26 serve as a working reference with which a chuck of apolishing apparatus contacts when the polishing jig 1 is mounted on thechuck and polished by the polishing apparatus. Particularly theparallelism of the lower face of the disk portion 26 has an influence onthe accuracy of finishing. With the polishing jig 1 of the presentembodiment, since the faces which serve as a working reference in thismanner are formed by precision working in advance, positioning on thepolishing apparatus can be performed accurately and high accuracypolishing can be anticipated.

A disk-shaped gripping portion 53 projects in a direction substantiallyperpendicular to the rotational center axis 21 from an outer face of thering-shaped portion 5. The gripping portion 53 has an outer diametergreater than a working object lens such that it projects outwardlyfarther than the working object lens when the working object lens isheld in a closely contacting relationship on the closely contactingportion 3. The gripping portion 53 has a function of being gripped by arobot hand when the polishing jig 1 is to be conveyed by the robot hand.

A recess 54 as an embodiment of a first engaging portion is provided onan outer periphery of the disk-shaped gripping portion 53. The recess 54is provided for positioning of the polishing jig 1 in the rotationaldirection. A conveyor tray hereinafter described has a projection as anembodiment of a second engaging portion for engaging with the recess 54when the polishing jig 1 is accommodated into the conveyor tray so thatthe polishing jig 1 can be accommodated accurately in a predetermineddirection of the conveyor tray. Consequently, when the gripping portion53 is gripped by a robot hand, it is directed in a predetermineddirection so that the polishing jig 1 may be mounted accurately in apredetermined direction on a chuck of a polishing apparatus.Accordingly, the shapes of the first and second engaging portions may beany shapes for engaging with each other, and it is possible, forexample, to form the first engaging portion as a projection and form thesecond engaging portion as a recess for engaging with the projection.Also it is possible to use a perforation and a projection which can befitted in the perforation.

Three positioning marks 55 are provided on an upper face of thedisk-shaped gripping portion 53 at different locations in thecounterclockwise direction at intervals of 90 degrees from the recess 54and extend radially from the rotational center axis 21.

The closely contacting portion 3 has a short-axis cylindrical shape andprojects upwardly farther than the gripping portion 53 of thering-shaped portion 5. An enlarged cross sectional view of the closelycontacting portion 3 is shown in FIG. 2. While the cross section of theclosely contacting portion 3 projecting from the gripping portion 53 hasa substantially rectangular shape, an upper portion of an inner wallface 31 of the closely contacting portion 3 is inclined a little towardthe rotational center axis 21 side from a direction (indicated by abroken line in FIG. 2) parallel to the rotational center axis 21. Theinner wall face 31 of the closely contacting portion 3 forms the fillinggap portion 4. Therefore, when adhesive substance is filled into thefilling gap portion 4, the inner wall face 31 of the closely contactingportion 3 serves as a reversely tapering pull-out preventing portionsince it exhibits an increasing width away from the opening of theclosely contacting portion 3. Consequently, even if solidified adhesivesubstance is exfoliated, for example, from the wall face of the fillinggap portion 4, there is no possibility that it may come off from thefilling gap portion 4. An upper face of the closely contacting portion 3is a portion which closely contacts with the convex surface of a workingobject lens, and a projection 32 having a triangular cross section isprovided on the upper face of the closely contacting portion 3 so as toallow contact along a line.

A small recess 33 is provided on the upper face of the ring-shapedclosely contacting portion 3 as shown in FIG. 1. The recess 33 functionsas an air bleeder for air to be discharged from the filling gap portion4 when adhesive substance is filled into the filling gap portion 4.Therefore, when adhesive substance is to be filled, adhesive substancein the form of liquid is filled from the lower side with the recess 33directed upwardly, and the filling of the adhesive substance is endedwhen the adhesive substance finally leaks out from the recess 33.

As shown in FIG. 1, an inner wall face 56 of the ring-shaped portion 5is formed in an inverted conical shape wherein the closely contactingportion 3 serves as an opening such that the diameter thereof decreasesdownwardly from the inner wall face 31 of the closely contacting portion3 until it is integrated with the hollow portion 22 of the mountingportion 2. Accordingly, the hollow portion 22 of the mounting portion 2and the filling gap portion 4 are communicated with each other.

A diametrically extending turning preventing groove 57 is provided onthe inclined inner wall face 56 of the ring-shaped portion 5. Theturning preventing groove 57 is communicated with the hollow portion 22of the mounting portion 2. The bottom face of the turning preventinggroove 57 is formed in a tapering state such that it has a width greaterthan that of an upper portion of the turning preventing groove 57. Sincethe inner wall face 56 of the ring-shaped portion 5 is formed in aninverted conical shape, when solidified adhesive substance is exfoliatedfrom the inner wall face 56, the turning preventing groove 57 preventsthe solidified adhesive substance from turning in the filling gapportion 4 thereby to allow accurate polishing. Accordingly, not only arecess but also a projection which projects from the inner wall face 56may be used only if it functions as a turning preventing element. Or,concaves and convexes may be provided on the inner wall face 31 of theclosely contacting portion 3.

In the polishing jig 1 shown in FIG. 1, the filling gap portion 4 intowhich adhesive substance is to be filled is formed from a portionsurrounded by a convex surface of a working object lens, the inner wallface 31 of the closely contacting portion 3, the inner wall face 56 andthe turning preventing groove 57 of the ring-shaped portion 5 and partof the inner wall face of the hollow portion 22 of the mounting portion2 when the convex surface of the working object lens closely contactswith the projection 32 of the closely contacting portion 3.

In order to hold a working object lens by means of the polishing jig 1of the present embodiment, the polishing jig 1 is disposed obliquelysuch that the recess 33 of the closely contacting portion 3 ispositioned highest within the filling gap portion 4. Then, a convexsurface 11 of the working object lens 10 is pressed strongly against thering-shaped closely contacting portion 3 with the center of the workingobject lens registered with the rotational center axis 21 as seen inFIG. 3. Then, molten low melting point metal 7 is poured as adhesivesubstance in the form of liquid through the hollow portion 22 of themounting portion 2 to fill up the low melting point metal 7 into thefilling gap portion 4. Thereafter, when the low melting point metal 7 issolidified, the low melting point metal 7 adheres to the convex surface11 surrounded by the ring-shaped closely contacting portion 3 of theworking object lens 10 and the wall faces which define the filling gapportion 4. Consequently, the working object lens 10 can be held on theclosely contacting portion 3.

If the working object lens 10 is held on the polishing jig 1 as shown inFIG. 3 and the mounting portion 2 is set in position, for example, onthe chuck 613 of such a numerically controlled machining apparatus 600as shown in FIG. 10 and then a concave surface 12 of the working objectlens 10 is machined by the numerically controlled machining apparatus600 while the working object lens 10 is rotated around the rotationalcenter axis 21, then the concave surface 12 of the working object lens10 can be shaped into a predetermined lens surface shape such as, forexample, that of a progressive surface.

Since the polishing jig 1 of the present embodiment can form a face,which serves as a polishing working reference, accurately and includesthe turning preventing groove 57 and the pull-out preventing portion 31,accurate polishing can be performed such that the play when the adhesivesubstance is solidified is little.

Further, since the polishing jig 1 includes the disk-shaped grippingportion 53, it is structured suitable for automation in that it can beautomatically conveyed by a robot hand. Further, since the polishing jig1 includes the recess 54 for positioning, it can contribute toautomation in that it can be positioned automatically in a rotationaldirection.

With such a polishing jig 1 as described above, it is difficult to holdthe working object lens 10 obliquely in order to provide a prism on theworking object lens 10 or hold the working object lens 10 in aneccentrically displaced state in order to eccentrically work the same,and therefore, such working is preferably performed in accordance with aprogram of the numerically controlled machining apparatus 600. However,the polishing apparatus in which the polishing jig 1 of the presentinvention is used is not limited to the numerically controlled machiningapparatus 600 shown in FIG. 10 but may be any numerically controlledpolishing apparatus which can perform cutting, grinding, mirrorpolishing and so forth of a spectacle lens. For example, the polishingapparatus may be a numerically controlled polishing apparatus forperforming mirror polishing.

Now, an embodiment of a conveyor tray of the present invention which isapplied to an application for accommodating and conveying such apolishing jig 1 of the present invention as shown in FIG. 1 is describedwith reference to FIG. 4.

The conveyor tray 100 is a tool for accommodating and conveying thepolishing jig 1 of the present invention in which such a working objectlens 10 as shown in FIG. 3 is held. If an impact is applied to theworking object lens 10 or the polishing jig 1 while the working objectlens 10 is held on the closely contacting portion 3 through the lowmelting point metal 7, then the working object lens 10 is sometimesseparated from the low melting point metal 7. The conveyor tray 100 hasa function of transporting the working object lens 10 while protectingit so that an impact may not be applied to it.

The conveyor tray 100 has such a shape that two trays each in the formof a tube of a substantially square shape for accommodating onepolishing jig 1 therein are connected to each other, and has aparallelepiped housing which is open at the top and the bottom thereof.A partition 102 is provided at a central portion of the conveyor tray100 in the longitudinal direction such that it separates the conveyortray 100 at the center of the conveyor tray 100 into left and rightaccommodation boxes 101, 101. The accommodation boxes 101, 101 have asame structure. Each of the accommodation boxes 101 has a quadrilateralplate 110 which is joined at an intermediate portion of an inner sideface of the accommodation box 101 in the heightwise direction integrallyto the inner side face therearound. A circular depression 111 having aninner diameter a little greater than the outer diameter of thedisk-shaped gripping portion 53 of the polishing jig 1 is provided atthe center of the quadrilateral plate 110, and an accommodation portion112 is provided as a ring-shaped offset raised from the depression 111on an outer peripheral portion of the circular depression 111. Theaccommodation portion 112 in the form of an offset receives a lower faceof an outer peripheral portion of the gripping portion 53 of thepolishing jig 1, and an outer circumferential face of the disks-shapedgripping portion 53 is positioned by an outer circumferential face ofthe depression 111. A through-hole 113 having a diameter greater thanthe disk portion 26 of the polishing jig 1 is perforated at a centralportion of the depression 111. The through-hole 113 allows passagetherethrough of a cylindrical ejecting jig 810 having an inner diametera little greater than the outer diameter of the cylindrical portion 23of the polishing jig 1.

A projection 115 is provided on an upper face of the accommodationportion 112 and serves as a second engaging portion for engaging withthe recess 54 of the gripping portion 53 of the polishing jig 1. Whenthe gripping portion 53 is accommodated into the accommodation portion112, the recess 54 must be fitted with the projection 115. Consequently,the polishing jig 1 can be accommodated while it is directed accuratelyin the reference direction.

Four recessed portions 116 are provided on the quadrilateral plate 110in such a manner as to split the accommodation portion 112. The recessedportions 116 allow an operation of gripping the gripping portion 53 ofthe polishing jig 1 with the fingers and accommodating it into theaccommodation portion 112.

A clip portion 120 is provided on an outer side face of the conveyortray 100 such that it can clip paper on which a bar code is recorded orsome other paper necessary for manufacture.

With such a conveyor tray 100 as described above, the gripping portion53 of a polishing jig 1 on which the working object lens 10 is held withthe recess 54 and the projection 115 engaged with each other can beplaced into each of the accommodation portions 112 and retained andconveyed safely so that the working object lens 10 of the polishing jig1 on which the working object lens 10 is held may not be hit by anyother article. For example, in a working area in which the workingobject lens 10 is mounted on the polishing jig 1, the polishing jig 1 onwhich the working object lens 10 is held can be placed into the conveyortray 100. Further, the conveyor tray 100 can be used to an applicationwherein it is conveyed from the working area to a place in the proximityof a polishing apparatus and, after polishing is performed by thepolishing apparatus, the polishing jig on which the worked lens is holdis accommodated back into the conveyor tray 100, whereafter the conveyortray 100 is conveyed as it is to a mirror polishing apparatus so thatmirror polishing is performed for the worked lens.

The operation of conveying the polishing jig 1 from the conveyor tray100 to the polishing apparatus and mounting the polishing jig 1 on thepolishing apparatus can be performed, for example, using a fingersection 820 of a robot hand as shown in (b) of FIG. 4. A polishing jig 1on which a working object lens 10 is held and which is held on theconveyor tray 100 transported by a conveyor or the like is stopped at aposition just above the ejecting jig 810 which normally assumes alowered position as shown in (b) of FIG. 4 but moves up when necessary.Then, the ejecting jig 810 is moved up. When the ejecting jig 810 passesthrough the through-hole 113 and receives the lower face of the diskportion 26 of the polishing jig 1 and then moves up with the polishingjig 1 placed thereon, the finger section 820 of the robot hand can gripthe gripping portion 53 and convey the polishing jig 1 to the polishingapparatus.

The polishing jig 1 conveyed from the polishing apparatus by the fingersection 820 of the robot hand as shown in (b) of FIG. 4 after thepolishing is completed is received by the upwardly moved ejecting jig810. Then, after the finger section 820 of the robot hand releases thepolishing jig 1, the ejecting jig 810 is lowered. Consequently, thegripping portion 53 of the polishing jig 1 can be placed andaccommodated back into the accommodation portion 112 of the conveyortray 100.

Therefore, the conveyor tray 100 of the present embodiment has astructure suitable for automatic conveyance.

The conveyor tray 100 can accommodate a pair of polishing jigs 1therein. In short, the conveyor tray 100 can convey left and rightspectacle lenses in pair. When only one of left and right spectaclelenses should be worked, only one lens is accommodated into the conveyortray 100. Since the conveyor tray 100 can accommodate a pair of lensesin pair, there is an advantage that, for example, lenses can be fed inpair to an inspection step and so forth at which the lenses must be inpair.

The polishing jig and the conveyor tray of the present invention are notlimited to the embodiments described above. While, for example, the gripportion has a disk-like shape, the shape of the grip portion is notlimited to a disk-like shape, but any shape may be used only if the gripportion can be gripped ready by a robot hand. Further, naturally themounting portion has a shape conforming with a chuck of a polishingapparatus by which it is mounted. Also the shape and so forth of theclosely contacting portion can be modified suitably. Furthermore, theshape of the conveyor tray may be modified suitably such that, forexample, it has recesses or the like at which the conveyor tray is to begripped by a robot hand, and also the shape and so forth of theaccommodation portion can be modified suitably. The conveyor tray is notlimited to that which accommodates two polishing jigs, but may bemodified so as to accommodate one or three or more polishing jigs.

Subsequently, an embodiment of a conveying method and a conveyingapparatus of the present invention is described.

According to the conveying method of the present invention, one workingobject article is taken out from a conveyor tray, in which one or pluralworking object articles are accommodated at individual accommodatedpositions, and is conveyed to and then stands by at a working apparatus.Then, another article worked by the working apparatus is carried outfrom the working apparatus, and the working object article in thestandby state is mounted on and worked by the working apparatus. Then,while the working object article is worked in this manner, the workingobject article carried out is returned to its original accommodationposition of the conveyor tray.

In the embodiment described below, an example wherein spectacle lensesheld on a polishing jig of the present invention are machined as workingobject articles is described.

Referring to FIG. 5, two numerically controlled machining apparatus 600shown in FIG. 10 are disposed. A conveyor system for conveying aconveyor tray in a horizontal direction includes a first conveyor 721, asecond conveyor 722 and a third conveyor 723. The first conveyor 721conveys a conveyor tray from a place at which a working object articleis accommodated into a conveyor tray to a place in the proximity of eachof the machining apparatus 600. The second conveyors 722 are disposedfor the individual machining apparatus 600 and each places a conveyortray at a place at which a working object article is carried into andout from the conveyor tray to the machining apparatus 600 or vice versa.The third conveyor 723 conveys a working object article for whichmachining is completed to a next step. A conveyor tray is fed from thefirst conveyor 721 to one of the second conveyors 722 by a first robothand 731, and fed from the second conveyor 722 to the third conveyor 723by a second robot hand 732. A working object article is conveyed betweeneach of the second conveyors 722 and the corresponding machiningapparatus 600 by a robot hand 800 serving as a three-dimensionalconveying means which grips the working object article.

An example of a finger section of a robot hand is shown in FIG. 6. Eachof the first robot hand 731 and the second robot hand 732 for feeding aconveyor tray is configured such that a finger section 734 of the robothand 730 grips the recesses provided on the side faces of the conveyortray 100 from the opposite sides to lift and feed the conveyor tray 100to another conveyor. Each of the second conveyors 722 includes rollers725 and 726 for individually supporting the opposite end portions in thewidthwise direction of the bottom face of the conveyor tray 100.Rotation of the rollers 725 and 726 is controlled to move the conveyortray 100 forwardly or backwardly and stop the conveyor tray 100 at apredetermined position.

(a) of FIG. 7 to (e) of FIG. 9 are flow charts illustrating operation ofa transfer means and operation of a conveying means when a workingobject article is taken out from a conveyor tray and conveyed to amachining apparatus and then the working object article after completionof machining is returned into the conveyor tray.

The transfer means includes a third robot hand 800 and an ejectionapparatus, and the conveying means includes a second conveyor 722. It isto be noted that the second conveyor 722 is omitted in FIGS. 7 to 9.

As shown in (a) of FIG. 7, the working object article is a workingobject lens 10, and the working object lens 10 is held at the convexsurface thereof by the polishing jig 1 of the present inventiondescribed hereinabove. The polishing jig 1 is mounted on the chuck 613of the numerically controlled machining apparatus 600 shown in FIG. 10and the concave surface of the working object lens 10 is machined by thecutting tool 624 or 625 of the machining apparatus 600. The polishingjig 1 includes a mounting portion 2 for being mounted on the chuck 613of the machining apparatus 600, a closely contacting portion 3 forholding the working object lens 10, and a gripping portion 53 swollen ina direction perpendicular to the rotational center axis of the mountingportion 2. The closely contacting portion 3 holds the convex surface ofthe working object lens 10, for example, through a metal having a lowmelting point. The gripping portion 53 of the polishing jig 1 is aportion to be gripped by a robot hand and projects outwardly fartherthan the working object lens 10.

The conveyor tray 100 which accommodates the polishing jig 1 has a formof a parallelepiped box open at the top and the bottom thereof as shownin FIG. 4 and is adapted to accommodate two polishing jigs 1 therein.Usually, each polishing jig 1 in which a pair of left and right workingobject lenses 10 are held is accommodated in one conveyor tray 100. Theconveyor tray 100 includes a ring-shaped accommodation portion 112 forreceiving an outer circumferential edge of the gripping portion 53 ofthe polishing jig 1 such that the gripping portion 53 is placed on theaccommodation portion 112 so that the polishing jig 1 can beaccommodated accurately into a predetermined accommodation position.

The ejection apparatus not shown includes a cylindrical ejecting jig 810which can receive the mounting portion 2 of the polishing jig 1 andcontact with the disk portion 26 (refer to FIGS. 1 and 4) and moves theejecting jig 810 upwardly and downwardly in a vertical direction. Whenthe ejecting jig 810 moves up, it receives the polishing jig 1 frombelow and lifts the polishing jig 1 so that the polishing jig 1 can beejected from the conveyor tray 100. The ejection apparatus performs anoperation of receiving, at the ejecting jig 810 thereof, the polishingjig 1 from the conveyor tray 100 and ejecting the polishing jig 1 so asto be transferred to the robot hand 800 and another operation ofreceiving, at the ejecting jig 810 thereof, the polishing jig 1 on whichthe worked lenses for which machining is completed are held from therobot hand 800 and returning the polishing jig 1 to the conveyor tray100. The ejecting jig 810 is disposed at one place of the secondconveyor 722. Accordingly, the position at which the ejecting jig 810 isdisposed is a transfer position 830 as a reference position at which thepolishing jig 1 is transferred.

The robot hand 800 includes two feeding and removing finger sectionswhich perform an operation of gripping the gripping portion 53 of thepolishing jig 1 and carrying the polishing jig 1 independently of eachother. The feeding finger section 821 performs an operation of grippingthe gripping portion 53 of the polishing jig 1 placed on the ejectingjig 810, carrying the polishing jig 1 into the machining apparatus 600and keeping the polishing jig 1 in a standby state at a standby position632 in the proximity of a machining zone 631. Further, the feedingfinger section 821 performs an operation of mounting the polishing jig 1standing by at the standby position 632 on the chuck of the machiningapparatus 600 when the removing finger section 822 (refer to (c) of FIG.8) releases the polishing jig 1, which holds working object lenses forwhich working is completed, from the chuck of the machining apparatus600. The machining apparatus 600 performs machining of the workingobject lens after the polishing jig is mounted on the chuck. On theother hand, the removing finger section 822 performs an operation ofgripping the gripping portion 53 of the polishing jig 1 which holds aworked lens for which machining is completed to remove the polishing jig1 from the chuck not shown of the machining apparatus 600 and conveyingand placing the polishing jig 1 to and onto the ejecting jig 810 at thelifted position.

The second conveyor 722 serving as the conveying means not shown in FIG.7 controls to move the conveyor tray 100 forwardly and backwardly in itslengthwise direction and stop the conveyor tray 100 at a predeterminedposition. The second conveyor 722 performs an operation of conveying aconveyor tray 100 which accommodates a polishing jig 1 on which workingobject lenses to be worked are held until the rotational center axis ofthe polishing jig 1 is disposed and stopped at a position just above thetransfer position 830, another operation of placing the originalaccommodation position of the conveyor tray 100 in which the polishingjig 1 on which hold one of the working object lenses for which machiningis completed was accommodated to a position just above the transferposition 830, and a further operation of conveying the conveyor tray 100including the two working object lenses for which working is completedto a position at which the conveyor tray 100 is to be transferred to thethird conveyor 723.

The numerically controlled machining apparatus 600 rotates the polishingjig 1 mounted on the chuck 613 and uses the cutting tool 624 or 625 tomachine the concave surface of a working object lens 10 into apredetermined shape under numerical control. The working time requiredfor machining of one working object lens 10 by means of the machiningapparatus 600 is several minutes.

An operation of returning, using such an apparatus as described above, apolishing jig 1 accommodated in a conveyor tray 100 to its originalaccommodation position after working object lenses 10 held on thepolishing jig 1 are machined by the machining apparatus 600 is describedwith reference to the flow charts of (a) of FIG. 7 to (e) of FIG. 9.

(a) of FIG. 7 shows a first conveyor tray 100 a on the leading side anda second conveyor tray 100 b on the trailing side in each of which twopolishing jigs are accommodated. A first polishing jig 1 a on which aworking object lens 10 is held is accommodated at a first accommodationposition 191 on the leading side of the first conveyor tray 100 a, and asecond polishing jig 1 b on which another working object lens 10 is heldis accommodated at a second accommodation position 192 on the trailingside of the first conveyor tray 100 a. A third polishing jig 1 c onwhich a further working object lens 10 is held is accommodated at athird accommodation position 193 on the leading side of the secondconveyor tray 100 b, and a fourth polishing jig 1 d on which a stillfurther working object lens 10 is held is accommodated in a fourthaccommodation position 194 on the trailing side of the second conveyortray 100 b. The accommodation positions 191 to 194 in this instance arepositions at each of which the rotational center axis 21 of the mountingportion 2 when a polishing jig 1 is placed on the accommodation portion112 exists.

First, the second conveyor 722 moves the first conveyor tray 100 aforwardly and stops the conveyor tray 100 so that the firstaccommodation position 191 on the leading side is disposed at thetransfer position 830 as shown in (a) of FIG. 7. The ejection apparatusmoves the ejecting jig 810 upwardly so that the ejecting jig 810receives and ejects the first polishing jig 1 a accommodated in thefirst accommodation position 191, and the feeding finger section 821 ofthe robot hand 800 grips and holds the first polishing jig 1 a. Thefeeding finger section 821 conveys the first polishing jig 1 a to themachining apparatus 600 and mounts the first polishing jig 1 a on thechuck of the machining apparatus 600. The machining apparatus 600 startsmachining of the working object lens 10 held on the first polishing jig1 a by means of the cutting tool 624 or 625.

Then, as shown in (b) of FIG. 8, during machining of the working objectlens 10 held on the first polishing jig 1 a, the ejecting jig 810 movesdown to its original position, and then the second conveyor 722 movesthe first conveyor tray 100 a forwardly until the second accommodationposition 192 is disposed at the transfer position 830. Then, theejecting jig 810 is moved upwardly and receives and ejects the secondpolishing jig 1 b, and the feeding finger section 821 of the robot hand800 which has conveyed the first polishing jig 1 a grips and holds thesecond polishing jig 1 b. The feeding finger section 821 conveys thesecond polishing jig 1 b into the machining apparatus 600 and stands byat the standby position 632 while it remains gripping the secondpolishing jig 1 b. Meanwhile, the ejecting jig 810 moves down to itsoriginal position. (b) of FIG. 8 illustrates such a situation asdescribed above.

Thereafter, as shown in (c) of FIG. 8, when machining of the workingobject lens held by the first polishing jig 1 a comes to an end, therobot hand 800 uses the removing finger section 822 to grip the firstpolishing jig 1 a and remove the first polishing jig 1 a from the chucknot shown. Thereafter, the feeding finger section 821 in the standbystate mounts the second polishing jig 1 b on the chuck. Then, themachining apparatus 600 starts machining of the worked lens 10 held onthe second polishing jig 1 b. Meanwhile, the removing finger section 822conveys the removed first polishing jig 1 a from the machining apparatus600 to the transfer position 830. At this time, the second conveyor 722retracts the first conveyor tray 100 a and disposes the firstaccommodation position 191, which is the original accommodation positionof the first polishing jig 1 a, at the transfer position 830. Then, theejecting jig 810 is moved up, and the removing finger section 822 of therobot hand 800 places the first polishing jig 1 a on the ejecting jig810.

Thereafter, as shown in (d) of FIG. 9, when the ejecting jig 810 movesdown, the first polishing jig 1 a is accommodated back into the firstaccommodation position 191 with the gripping portion 53 thereof receivedby the accommodation portion 112 of the first conveyor tray 100 a. Theejecting jig 810 moves down as it is to its original position.Thereafter, the second conveyor 722 moves the first conveyor tray 100 aand the second conveyor tray 100 b forwardly until the thirdaccommodation position 193 of the second conveyor tray 100 b is disposedat the transfer position 830. Then, the ejecting jig 810 moves up toreceive and lift the third polishing jig 1 c, and the feeding fingersection 821 of the robot hand 800 grips the third polishing jig 1 c.Then, the feeding finger section 821 conveys the third polishing jig 1 cto the standby position 632 in the machining apparatus 600 and leavesthe polishing jig 1 standing by at the standby position 632. In themeantime, the machining apparatus 600 performs machining of the workingobject lens secured to the second polishing jig 1 b.

Then, as shown in (e) of FIG. 9, when machining of the working objectlens secured to the second polishing jig 1 b comes to an end, theremoving finger section 822 of the robot hand 800 removes the secondpolishing jig 1 b from the chuck and then the feeding finger section 821mounts the third polishing jig 1 c in the standby state on the chuck.Then, the machining apparatus 600 starts machining of the working objectlens secured to the third polishing jig 1 c. In the meantime, theremoving finger section 822 of the robot hand 800 conveys the grippedsecond polishing jig 1 b to the transfer position 830. At this time, thesecond conveyor 722 disposes the second accommodation position 192 whichis the original accommodation position of the second polishing jig 1 bat the transfer position 830. Then, the ejecting jig 810 moves up toreceive the second polishing jig 1 b from the removing finger section822, and then when the ejecting jig 810 moves down, it returns to itsoriginal position while it accommodates the second polishing jig 1 bback into the second accommodation position 192.

Thereafter, the same sequence of operations is repeated to repeatconveyance of the fourth polishing jig 1 d to the transfer position 830,removal of the third polishing jig 1 c with regard to which machiningcomes to an end and mounting of the fourth polishing jig 1 d, returningof the third polishing jig 1 c to the third accommodation position 193and conveyance of a fifth polishing jig not shown to the transferposition 830.

In short, a working object article accommodated at an accommodationposition just on the trailing side of an empty accommodation position inwhich a working object article being worked has been accommodated isconveyed to the standby position, and the worked article for which theworking is completed is returned to the accommodation position just onthe preceding side of the accommodation position in which the workingobject article being worked has been accommodated.

It is to be noted that, where only one polishing jig 1 is accommodatedin the conveyor tray 100, an empty accommodation position is notselected based on information of a bar code attached to the conveyortray 100.

In this manner, according to the conveying method and the conveyingapparatus of the present embodiment, a polishing jig stands by at astandby position, and another polishing jig on which hold a worked lensfor which working is completed and the polishing jig in the standbystate are exchanged rapidly and working of a working object lens held onthe polishing jig is started. Then, within the working time, thepolishing jig on which the worked lens is held and the polishing jig onwhich the working object lens is held are exchanged and the polishingjig is placed into a standby state. Therefore, also when the polishingtime is long, working can be performed efficiently.

Further, according to the conveying method and the conveying apparatusof the present embodiment, a polishing jig taken out from a conveyortray so as to be used for working is returned into the sameaccommodation position of the same conveyor tray after the working.Therefore, a pair of polishing jigs accommodated in a conveyor traybefore working are maintained as they are also after the working.

According to the conveying method and the conveying apparatus of thepresent embodiment, since the ejection apparatus is used to performejection of a polishing jig from a conveyor tray and accommodation of aworked article into the conveyor tray at the transfer position, theconveyor for conveying a conveyor tray is controlled to position theconveyor tray. According to this method, there is an advantage that theapparatus is simplified when compared with an alternative case wherein arobot hand is controlled so that a worked article is conveyed to apredetermined accommodation position for a conveyor tray by means of therobot hand or a robot hand performs a complicated operation so that apolishing jig is taken out from a conveyor tray.

The conveying method and the conveying apparatus of the presentinvention are not limited to the embodiment described above. Forexample, while an example wherein a spectacle lens carried on apolishing jig is machined is described hereinabove, the presentinvention is not limited to the particular example, but can be appliedalso to some other processing such as when a lens is machined or when alens is mirror polished. Further, while the conveyor tray describedaccommodates two polishing jigs, it may otherwise accommodate one orthree or more polishing jigs.

INDUSTRIAL APPLICABILITY

The polishing jig of the present invention is used as a jig for mountinga working object spectacle lens on an apparatus for polishing the innersurface of a spectacle lens and can be used to an application formanufacturing a spectacle lens.

The conveyor tray of the present invention has an application wherein itaccommodates such a polishing jig as described above and protects andconveys the polishing jig, and therefore can be used to an applicationwherein a spectacle lens is manufactured.

According to the conveying method of the present invention, a workingobject article is taken out from such a conveyor tray as described aboveand conveyed into a working apparatus, and the worked article with whichthe working is completed is returned to the conveyor tray. Therefore,the conveying method can be utilized for manufacture of a spectacle lensapplying a spectacle lens as the working object article.

The conveying apparatus of the present invention can be used for anapplication wherein, for example, a spectacle lens is manufactured.

DESCRIPTION OF REFERENCE NUMERALS

-   1 polishing jig-   2 mounting portion-   3 closely contacting portion-   31 inner wall face (pull-out prevention portion)-   4 filling gap portion-   5 ring-shaped portion-   53 gripping portion-   54 recess-   57 turning preventing groove-   10 working object lens-   100 conveyor tray-   112 accommodation portion-   113 through-hole-   115 projection-   600 machining apparatus-   722 conveying means-   800 transfer means-   810 ejecting jig-   830 transfer position-   191 to 194 accommodation position

1. A polishing jig, comprising: a mounting portion to be mounted on achuck of a polishing apparatus which performs polishing of a concavesurface of a working object lens; a ring-shaped closely contactingportion, for closely contacting with a convex surface of the workingobject lens; and a filling gap portion having an opening at said closelycontacting portion for being filled with adhesive substance whichadheres to the convex surface of the working object lens closelycontacted by said closely contacting portion and surrounded by saidclosely contacting portion to hold the working object lens, wherein saidpolishing jig further comprises a gripping portion which projectsoutwardly farther than the working object lens in a directionsubstantially perpendicular to a rotational center axis of said mountingportion.
 2. A polishing jig according to claim 1, wherein a firstengaging portion for positioning is provided on said gripping portion.3. A polishing jig according to claim 1, wherein a turning preventingprojection or recess is provided on a wall face which defines saidfilling gap portion.
 4. A polishing jig according to claim 1, wherein apull-out preventing portion having a width which increases away fromsaid opening of said closely contacting portion is provided on a wallface which forms said filling gap portion.
 5. A conveyor tray in theform of a box open at the top thereof for containing a polishing jigwhich has a mounting portion to be mounted on a chuck of a polishingapparatus, a ring-shaped closely contacting portion for closelycontacting with a working object lens, a filling gap portion having anopening at said closely contacting portion for being filled withadhesive substance, a gripping portion projecting outwardly farther thanthe working object lens in a direction substantially perpendicular to arotational center axis of said mounting portion, and an engaging portionfor positioning provided on said gripping portion, the polishing jigholding a working object lens via the adhesive substance filled in saidfilling gap portion, said conveyor tray comprising: an accommodationsection for receiving an outer peripheral portion of said grippingportion of said polishing jig; a through-hole for passing therethroughan ejecting jig which receives said polishing jig placed on saidaccommodation portion and moves up and down together with said polishingjig; and a second engaging portion for engaging with said first engagingportion.
 6. A conveyor tray according to claim 5, wherein said conveyortray accommodates two such polishing jigs.
 7. A conveying method,comprising: from within a conveyor tray in which one or a plurality ofworking object articles are accommodated at respective accommodationpositions, taking out one of the working object articles and conveyingthe working object article to a working apparatus so that the workingobject article thereafter stands by in said working apparatus; carryingout a worked article worked by said working apparatus from said workingapparatus and mounting the working object article in the standby stateon said working apparatus so as to be worked by said working apparatus;and returning the worked article to an original one of the accommodationpositions of said conveyor tray while the working object article isbeing worked.
 8. A conveying method according to claim 7, wherein aworking object article accommodated in said conveyor tray is taken outat a predetermined transfer position, and the worked article is returnedto the original accommodation position of said conveyor tray at thetransfer position.
 9. A conveying method according to claim 7, whereinsaid conveyor tray accommodates a pair of working object articles.
 10. Aconveying method according to claim 7, wherein the working objectarticle is a working object lens held on a polishing jig, and saidworking apparatus is a lens polishing apparatus.
 11. A conveyingapparatus comprising: transfer means for conveying a working objectarticle, accommodated in a conveyor tray disposed at a particulartransfer position, from the transfer position to a working apparatus sothat the working object article thereafter stands by in said workingapparatus, taking out a worked article for which working by said workingapparatus is completed, mounting the working object article in a standbystate on said working apparatus, and accommodating the worked articleinto the conveyor tray conveyed to and disposed at the transferposition; and conveying means for conveying the conveyor tray whereinone or a plurality of working object articles are accommodated atrespective accommodation positions, successively disposing theaccommodation positions for the working object articles at the transferposition and disposing, when said transfer means conveys the workedarticle to the transfer position, the accommodation position in whichthe worked article was accommodated at the transfer position.
 12. Aconveying apparatus according to claim 11, wherein said transfer meanscomprises: an ejection apparatus for receiving the working objectarticle at the transfer position and moving upwardly and downwardlytogether with the working object article; and three-dimensionalconveying means for conveying the working object article placed on saidejection apparatus to said working apparatus so that the working objectarticle thereafter stands by in said working apparatus, taking out theworked article for which working by said working apparatus is completed,mounting the working object article in the standby state on said workingapparatus, and conveying the worked article to the transfer position, atwhich said three-dimensional conveying means places the worked articleonto said ejection apparatus.